Since my tank is plastic tub how can i see if the male is eating the egg or not, i cant see because the tank is not transparent and the eggs is located at stryofoam cup. I cant see clearly. The eggs not too much i think. Because the female is small,so she lay eggs at whole stryofoam cup only.

I don't think you should remove the cup. It could damage the bubblenest, and since you mentioned that the nest is small, removing it could possibly destroy the whole nest. And I agree with the others, please research before breeding. Breeding is a big responsibility.(;